1. Field of the invention
The invention concerns a device for sealing the gap between the rotor blades and the casing of a turbomachine, configured with a conical profile, in which the rotor blades are provided with circumferential shroud plates, which seal by means of serrations against the casing with the formation of radial gaps.
2. Discussion of Background
Devices of this type are known. They consist essentially of shroud plates with serrations running in the circumferential direction and sealing against the casing or against a honeycomb arrangement. They form a see-through or a stepped labyrinth with purely radial gaps. As a rule, these shroud plates extend over the whole of the blade axial chord. A known sealing configuration of this type, having two sealing serrations, is represented by the first stage rotor blades in FIG. 1, which will be described later.
A disadvantage with these sealing configurations are the two large vortex spaces which are formed in front of and behind the serrations and result in a large dissipation. In addition, the open spaces render the cooling of the shroud plates more difficult.